Combined hand and stationary conduit-bender



-R. H. HENDERSON.

COMBINED HAND AND STATIONARY CONDUIT BENDER.

APPLICATION FILED JUNE5. 1919.

1 ,379,01 6, l A Patented May 24, 1921.

2 SHEETS-SHEET l.

W 71 ATTORA/Eii R. H. HENDERSON.

COMBINED HAND AND STATIONARY CONDUIT BENDER. APPLICATION FILED JUNE5, 1919.

79 01 6. Patented Mary 24, 1921.

2 SHEETS-SHEET 2.

FIG. '7

WITNESSES: INVENTOR:

UNITED STATES PATENT ornca.

ROBERT HALSEY HENDERSON, OF EAST ORANGE, NEW JERSEY.

COMBINED HAND AND STATIONARY CONDUIT-IBENDER.

' Application filed June 5, 1919. Serial No. 302,038.

To all whom it may concern:

Be it known that I, Roena'r HALSEY HEN- DERSON, a citizen of the United States, and

resident of East Orange, in the county of Essex and State of New Jersey, ha ve in- "ented certain new and useful Improvements in Combined Hand and Stationary Conduit-Benders; and I do hereby declare that the following description of my invention, .taken in connection with the accompanying' sheets of drawings, form a full, clear, and exact specification, which will enable others skilled in the art to which the said invention appertains to make and use the same.

This invention has general reference to pipe bending tools; and it consists, essentially, in the novel and peculiar combination of parts and details of construction, as

hereinafter first fully set forth and described, and then pointed out in the claims.

The object of this invention is the pro-. duction of an eflicient, serviceable, and comparatively inexpensive device, which though capable of being used for general pipe and rod bending purposes, is especially well adapted for employment as a conduit bender for electricians for house and factory wiring purposes. In the majority of cases, house wiring for electric lighting purposes, requires but one or two sizes of-iron pipe to receive the electric conductors; and it is especially for this class of work for which the present invention is designed.

In the drawings which illustrate this invention very fully, and form a part of this specification- Figure 1 is an elevation of one side of this tool. Fig. 2 is a similar view of the opposite side thereof. Fig. 3 is an elevation of one end, and Fig. 4 is a similar view" of the other end of this device. Fi 5 is a sectional view on line 5--5 of Fig. 4. Fig. 6 is a view of the device as applied to the top of a bench or other stationary object to convert this device into a stationary bender, the view being in the direction of an arrow applied to Fig. 1. Fig. 7 is a view showingthe application of the bender as applied to a vertically disposed stationary object, and the method of using the bender.

Like parts are designated by the same characters and symbols of reference in all the figures.

This conduit bender comprises a main portion A, which terminates in a cylindrcal shank B, which is externally screwthreaded as at 12, to receive a couplin or other sleeve C, wherewith en ages a s ort plece of commercial iron 'pipel), which pipe forms a convenient handle for manipulatmg the bender.

The main portion A is a curved element 13, the periphery of which is approximately semiclrcular; and this portion is formed integrally with two parallel flanges 14, 15, spaced apart at a distance substantially equivalent to the diameter of conduit or pipe E to be bent, to permit the latter to be seated between these flanges with a close, shdlng fit, whereby a deep groove 16 is formed, the depth of which groove exceeds the cross-sectional radius of the pipe to be bent the 'cross-sectional curvature of the bottomfof which conforms substantially to the cross-sectional circumference of the condult or pipe-Et'o'be bent, while the longitudlnal curvature of the portion 13 is considerably less than the curvature of an elbow or other bend that may be formed in the conduit or pipe E. r.

. The flange 15 has an extension 17, which terminates. in a post 18, which ost is of a height slightly less than thewidth of the groove 16, and it is spaced from the curved element '13 just far enough to permit the pipe E beingrpassed through the space 19, indicated in igs. 1 and 6, between the post 18 and the flange 14.

Approximately centrally, there is in the member A, and in the flanges a throughopening 20, and on the side 15 of the instrument there is a rib or projection 21, which reaches to the end of the extension 17 and has a two fold object, viz, to strengthen the member 17, and then to afford means which prevent rotation of the instrument when used as a stationary bender. Thus when this device is secured to a wooden bench or other like "object F, Fig. 6, by a bolt or lag screw 22, this rib will be partly embedded in the bench, whereby the device will resist any reasonable force which may be applied thereto when-a conduit is being formed.

To operate this device as a hand bender, a pipe is generally placed upon the floor and the pipe passed through the space 19, or the device is first placed onto the pipe and then placed on the floor. The operator now steps on the pipe and pulls on the handle D a short pull, which causes the post 18 to iii impinge on the pipe at the corner 23, said pipe extending thence between the flanges 14 and 15 into the groove 16 in the instrument so that the pipe will impinge directly upon the bottom of said groove and the sides of the pipe will impinge respectively upon the flanges 14: and 15, and then takes a short bite on the pipe by pressing downwardly upon the handle lever D. The downward swing of the handle lever D serves to roll the curved element 13 upon the pipe at the same time lifting the post 18 to bend the pipe upward from the fulcrum provided by the point of impingement of said curved element 13 with the pipe. As the post 18 lifts the pipe the latter bends upwardly, and as'the bend continues to form the curved element rolls back upon the unbent portion of the pipe, so that said fulcrum continuously shifts back simultaneously with the upward bending of the pipe. By reason of the fact that the groove 16 and flanges 14: and 15 snugly fit the cross-sectional contour of the side of-the pipe toward the curved element 13 coupled with the backward rolling movement tending to constantly shift the fulcrum from which the bend springs, the pipe is firmly held at the fulcrum or point of impingement with the curved element so that no permanent distortion, kinking, or collapse of the pipe can occur, the specified structure of the curved element 13 permitting such fitted relation of the pipe thereto being of the greatest importance in the present case, and affording one of the most important features of my improved pipe bender, as distinguished from other types of hand benders heretofore used. He then moves the instrument a distance toward himself and takes another bite and this step by-step operation of the device is continued until the proper bend in the pipe is attained. By a succession of these steps, it is not only possible to produce right-angled elbows, but also return bends, and as a matter of fact, apipe. coil having one or more convolutions can be readily produced and when completed, the bender removed from the formed article by a slight backward movement of the handle to pass the pipe sidewise through the gap 19.

When the device is to be used as a stationary bender, prefer to place the same in vertical position against the side of a post or other fixed object Fa, and fasten it removably thereto by the bolt or lag screw 22 in such manner that the handle D of the bender extends downwardly at an angle of approximately 45 degrees, with the end of the handle resting upon the floor, as shown in Fig. 7. in this manner the handle serves as a very strong and effective brace to prevent rotation of the bender when down n'ardly acting force is applied directly to aramie the conduit at its unbent end by the operator. And it may now be noted, that by simply removing the lag screw 22, the device is instantly converted into the hand bender hereinbefore described.

It is obvious that when the device is used as a stationary bender, the conduit E will be moved step by step and short bends made until the proper curvature is obtained, and

that the operator can produce the most difficult bends because the conduit is always in plain sight so that he can govern his actions accordingly.

Attention is now invited to the fact that in this instrument there are combined a forming, a bending, and a holding element,

made possible by the deep groove 16 having the parallel sides formed by the flanges 15, 16, said sides extending well above the middle-of the pipe to be bent as it rests in the .bottom of the groove, which sides of the bility of the bender shifting while the pipe is being bent. But as soon as the handle is released, the pipe will, owing to its elasticity and resiliency, resume its original round contour, so that the instrument can be moved along the pipe. By thus confining the pipe between the parallel sides ofthe flanges, the pipe cannot be permanently flattened, butwill always regain its original contour as soon as'pressure on the handle is removed.

In cases where an operator has to make a large number of bends, or bends of a complicated or difficult nature, it will be found that the stationary bender is the more desirable device to use, for the reason already referred to that the pipe is always in plain sight of the operator so that he can manipulate the pipe in the most effective manner. In this case the handle D, which is best made of one inch commercial wrought iron pipe of forty inches in length, is not actively engaged in the bending of the pipe, but the unbent portion of the pipe is used for this purpose in an obvious manner. it is necessary that a separate bender is used for every dilferent size of pipe, except perhaps when 3; and s inch pipe are to be bent. These two sizes of pipe have comparatively thick walls which do not readily flatten or kink when being bent, provided the angle of the bend is not too acute, so that the bender which is titted for inch pipe can be used for the smailer sizes of pipe; but for all sizes above inches up to and including 1 inch pipe,

a separate bender isto be employed which is especially fitted to receive the size of pipe under consideration. And in this connection it may be stated that approximately 75% of all the conduits used in house wiring are of the size of inch.

The entire bender, except the coupling and the handle is an integral casting in malleable iron or steel; its weight is less than two pounds, and it can, therefore, be cheaply manufactured, requiring no other machining than the screw-threading 12 at the end of the shank B, so that this article of manufacture can be sold at a very reasonable price. Being, as it is, as light as stated, it can be easily carried in every mechanics tool bag or tool chest, and be ready for instant use.

Having thus fully described this invention, I claim as new, and desire to secure to myself by Letters Patent of the United States 1. A pipe bender, comprising a curved element terminating in a' shank adapted to receive a handle, said element having inte-- gral parallel side flanges providing with said element a peripheral groove substantially conforming in width to the diameter of the pipe to be bent and which where the bending operation occurs is deeper than the radius of said pipe whereby tendency of the latter to expand laterally under bending strains causes the same to be gripped be-.

tween said side flanges to thereby prevent kinking or collapsing thereof, and one of said flanges having an extension provided with a transverse abutment post spaced outwardly from the forward end of said groove to provide an entrance gap between the former and the latter.

2. A pipe bender, comprising a curved element terminating in a shank adapted to receive a handle, said element having integral parallel side flanges providing with said element a peripheral groove conforming to the 'contour of the pipe to be bent and which where the bending operations occur is deeper than the radius of the latter, the relative s acin and outward extension 'of said flanges being such that they will impinge upon diametrically opposite points of the sides of said pipe entered and entering therein during the bending operation to pro-.

vide a lateral embracement thereof as the bending operation is initiated and continues,

one of said flanges having anoutward extension in the plane thereof and projecting forwardly from said curved element, and a transverse abutment post carried by said extension to project toward the opposing flange and spaced outwardly from the periphery of the latter to provide an entrance between said post and the forward end of said receiving groove.

3. A pipe bender, comprising a curved element terminating in a shank adapted to receive a handle, said curved element having spaced parallel side flan es at its periphery, said element and its anges providing a groove to receive the pipe to be bent, one of said side flanges having an extension provided with a transverse abutment post spaced outwardly from the forward end of said groove to provide an intermediate opening for entering said (pipe in said forward end of said groove, an the peripheral shape of said flanges being such that said groove is of less depth than the radius of the pipe to be bent at the forward end opposite said post but increasing in depth rearwardly to an extent greater than the radius of said pipe whereby the latter is gripped by said flanges and held against undue lateral expansion at all points within the arc of the bending operation.

4. The combination with a fixed support of a pipe bender having a transverse opening to receive a bolt for securing the same to said support, said bod having a lever portion serving when sai body is attached to said support as a stay, said body providing a curved element having spaced parallel side flanges at its periphery, said element and its flanges providing a groove to receive the pipe to be bent, one of said side flanges having an extension provided with a transverse abutment post spaced outwardly from the forward-end of said groove to provide an intermediate opening for entering pipe into the latter, and the peripheral shape of said flanges being such that said groove at and beyond the bending point is greater in de th than the radius of said pipe whereby the Fat ter is gripped by said flanges and held against undue lateral expansion at all points within the arc of the bending movement.

In testimony that I claim the foregoing as my invention, I have hereunto set my hand.

ROBERT HALSEY HENDERSON. 

